19 Juillet 2012
The Humpback whale (Mégaptera Novaeangliae) is a marine mammal that frequents the Polynesian waters between the months of end July and October. It is rather distinguishable due to its very long pectoral fins that measure one third of its body.
Seen for the first time in 1750, the Humpback whale is the slowest swimming species of the whale family in the world. It can measure up to 49ft and 15 tons. The oldest specimen ever observed was 50 years old.
The Humpback whale has a gigantic caudal fin spanning 13 feet that propels its body through the water at a speed of 10km/h. Its dorsal fin seems really tiny compared to its caudal fin. It presents a flat black rostrum (beak) shaped with humps used as sensors to scan its environment. Its jaw possesses 500 baleen plates (comb-like “teeth”) to filter its food. The Humpback whale has monochromatic vision in and out of the water and two little ear canals behind its eyes. In fact, the whale hears better than it sees. It takes in air from two large blowholes on its brow. The Humpback whale can replace 75% of its air with only one inhalation. For longer breath-holds underwater, whales had developed the ability to stock air in their muscles and blood and to giving priority to its vital organs for oxygenation.
The Humpback whales migrate every year to guarantee the survival of the species. They are guided by their instincts that draw them to tropical seas for the winter and to polar regions during the summer. They live in the Antarctic Ocean from January to May to take advantage of the ice melt that liberates tons of krill, its main source of food. During winter, the Antarctic Ocean becomes too cold for newborn whales which is why Humpback whales migrate in search of more clement tropical regions to give birth to their young. Every year, whales follow the same migration« path » as though it were in their genetic make-up.
This migration period is also the opportunity to hear the males singing. There is something mystical to these songs because all males coming from the same oceanic region “sing” the same “song” as if they were following a common partition. It is an unexplained phenomenon that the same song could be hear these whales song in French Polynesia between Tahiti and Moorea during the migration season.
© Photos - S.Girardot